Efficient expression of membrane-bound water channel protein (Aquaporin Z) in Escherichia coli

Protein Pept Lett. 2008;15(7):687-91. doi: 10.2174/092986608785133717.

Abstract

In order to explore the possibility of preparing a high-efficiency aquaporin-based biofilter, an efficient approach for expression of membrane-bound Aquaporin Z (AqpZ) in E. coli was proposed. The AqpZ gene was amplified by means of PCR, and two expression vectors (pET28-AqpZ and pET32-AqpZ) were constructed. The channel protein of interest was synthesized in E. coli BL21(DE3)/pET32-AqpZ as an insoluble fusion protein linked with trxA. However, with BL21(DE3)/pET28-AqpZ, significant amount of AqpZ fused only with 6-His (6-His-AqpZ) could be expressed, correctly folded and targeted into the membrane. Under the optimized culture conditions, the highest expression level (9.05 mg/l) of membrane-bound 6-His-AqpZ was achieved with BL21(DE3)/pET28-AqpZ, and an additional amount (2.35 mg/l) was expressed concomitantly as the inclusion body form. This expression result was 3.5 times higher than that in the previous studies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aquaporins / genetics*
  • Aquaporins / isolation & purification
  • Aquaporins / metabolism*
  • Base Sequence
  • Cell Membrane / metabolism
  • Cloning, Molecular
  • DNA, Bacterial / genetics
  • Escherichia coli / genetics*
  • Escherichia coli / growth & development
  • Escherichia coli / metabolism*
  • Escherichia coli Proteins / genetics*
  • Escherichia coli Proteins / isolation & purification
  • Escherichia coli Proteins / metabolism*
  • Gene Expression
  • Genes, Bacterial
  • Genetic Vectors
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / isolation & purification
  • Recombinant Fusion Proteins / metabolism

Substances

  • Aquaporins
  • DNA, Bacterial
  • Escherichia coli Proteins
  • Recombinant Fusion Proteins
  • aqpZ protein, E coli